The present disclosure generally relates to a rock crushing machine, such as a rock crusher of configurations commonly referred to as gyratory or cone crushers. More specifically, the present disclosure relates to a spider for use in a gyratory crusher or cone crusher including multiple spider arms each including an open channel formed between two spaced flanges.
Rock crushing machines break apart rock, stone or other materials in a crushing cavity formed between a downwardly expanding conical mantle installed on a mainshaft that gyrates within an outer upwardly expanding frustoconically shaped assembly of concaves inside a crusher shell assembly. The conical mantle and the mainshaft are circularly symmetric about an axis that is inclined with respect to the vertical shell assembly axis. These axes intersect near the top of the rock crusher. The inclined axis is driven circularly about the vertical axis thereby imparting a gyrational motion to the mainshaft and mantle. The gyrational motion causes points on the mantle surface to alternately advance toward and retreat away from the stationary concaves. During retreat of the mantle, material to be crushed falls deeper into the cavity where it is crushed when motion reverses and the mantle advances toward the concaves.
A spider is attached to the top of the shell assembly, forming the top of the support structure for the mainshaft. The material to be crushed is typically dropped onto an abrasion resistant spider arm shields that are positioned over the arms and central hub of the spider, after which the material to be crushed falls into the crushing cavity. The spider includes a central hub and bushing that receive one end of the mainshaft. The crushing forces generated in the crushing cavity create very large loads that are imposed in part on the spider. The spider must be constructed to withstand such loads to avoid having to shut down a crushing line, or an entire mine, to replace and/or repair a damaged spider.